Question

A circuit consist of two parallel circuit. having a resistance 20ohm and 30ohm respectively connected in series with 15ohm.the current through 15 ohm resistor is 3amps,then find the current through 20ohm and 30ohm resiator respectively..​

Answer 1

Equivalent resistance in parallel will be..  

1/R = 1/20 + 1/30  

1/R = 5/60  

R = 12 ohms  

Now, this us connected in series with 15 ohm resistor,  

R = 12+15 = 27 ohm  

Now, Total 3 A current passes through 15 ohm connect.

So, V = 3*27 = 81 ohms...(1)

Therefore, current through 30 ohm resistance will be.  

81/30 = 2.7 A  

Current through 20 ohm resistance will be.  

81/20 = 4.05 A.